Modern radiotherapy of cancer has begun to enter the era of precise treatment, therefore, to achieve accurate image guidance and control the absorbed dose of radiation to make a good treatment plan with a high degree of matching is very important. As shown in FIG. 1, the radiotherapeutic device in the prior art includes a gantry 904, a therapeutic head 900, and a first detector 901 corresponding to the therapeutic head 900, and a set of image guidance device comprising a cone beam generator 902 and a second detector 903 corresponding to the cone beam generator 902. Wherein the therapeutic head 900 emits therapeutic radiation for treatment of the tumor. The primary function of the first detector 901 is to detect whether the dose of the radiation emitted from the therapeutic head 900 matches the dose of the patient's treatment plan, i.e. dose verification. The image guidance system is configured to perform real-time positioning of the patient prior to treatment or during treatment, wherein the primary function of the second detector 903 is to detect the x-rays emitted by the cone beam generator 902 and passed through the patient, to form images of the regions related to the tumor.
The cost of the radiotherapeutic device will increase while employing multiple detectors since the price of the detector is high. In addition, the detector has a limited service life in a ray-irradiated environment and, and it is necessary to carry out overhaul or replacement of the multiple detectors in the future maintenance of the equipment, which further increases the cost.